java runtime problems

From:

Johnny Danger <jpaez1020@gmail.com>

Newsgroups:

comp.lang.java.programmer

Date:

Fri, 21 Sep 2007 06:00:35 -0000

Message-ID:

<1190354435.325358.178860@n39g2000hsh.googlegroups.com>

Hello all. I have a very simple problem. I am seeking to develop
java apps on mepis linux (ver. 3.4-3). I have installed jdk 1.6.0 and
i am having runtime error problems. It seems like a simple matter,
but i do not know how to solve the problem i am having. I have
compiled the following code directly from the sun website...

package start;

/*
* HelloWorldSwing.java requires no other files.
*/
import javax.swing.*;

public class HelloWorldSwing {
    /**
     * Create the GUI and show it. For thread safety,
     * this method should be invoked from the
     * event-dispatching thread.
     */
    private static void createAndShowGUI() {
        //Create and set up the window.
        JFrame frame = new JFrame("HelloWorldSwing");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        //Add the ubiquitous "Hello World" label.
        JLabel label = new JLabel("Hello World");
        frame.getContentPane().add(label);

        //Display the window.
        frame.pack();
        frame.setVisible(true);
    }

    public static void main(String[] args) {
        //Schedule a job for the event-dispatching thread:
        //creating and showing this application's GUI.
        javax.swing.SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                createAndShowGUI();
            }
        });
    }

}

when i compile, nothing seems to be wrong...

Aesotericon@5[HelloWorldSwing]$ ls
HelloWorldSwing.java
Aesotericon@5[HelloWorldSwing]$ /home/Aesotericon/Documents/jdk1.6.0/
bin/javac HelloWorldSwing.java
Aesotericon@5[HelloWorldSwing]$ ls
HelloWorldSwing$1.class HelloWorldSwing.class HelloWorldSwing.java
Aesotericon@5[HelloWorldSwing]$

when i try to run the program the following happens...

Aesotericon@5[HelloWorldSwing]$ /home/Aesotericon/Documents/jdk1.6.0/
bin/java HelloWorldSwing
Exception in thread "main" java.lang.NoClassDefFoundError:
HelloWorldSwing (wrong name: start/HelloWorldSwing)
        at java.lang.ClassLoader.defineClass1(Native Method)
        at java.lang.ClassLoader.defineClass(ClassLoader.java:620)
        at
java.security.SecureClassLoader.defineClass(SecureClassLoader.java:
124)
        at java.net.URLClassLoader.defineClass(URLClassLoader.java:
260)
        at java.net.URLClassLoader.access$000(URLClassLoader.java:56)
        at java.net.URLClassLoader$1.run(URLClassLoader.java:195)
        at java.security.AccessController.doPrivileged(Native Method)
        at java.net.URLClassLoader.findClass(URLClassLoader.java:188)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
        at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:
276)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:251)
        at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:
319)
Aesotericon@5[HelloWorldSwing]$ /home/Aesotericon/Documents/jdk1.6.0/
bin/java .HelloWorldSwing
Exception in thread "main" java.lang.NoClassDefFoundError: /
HelloWorldSwing
Aesotericon@5[HelloWorldSwing]$ unset CLASSPATH
Aesotericon@5[HelloWorldSwing]$ /home/Aesotericon/Documents/jdk1.6.0/
bin/java HelloWorldSwing
Exception in thread "main" java.lang.NoClassDefFoundError:
HelloWorldSwing (wrong name: start/HelloWorldSwing)
        at java.lang.ClassLoader.defineClass1(Native Method)
        at java.lang.ClassLoader.defineClass(ClassLoader.java:620)
        at
java.security.SecureClassLoader.defineClass(SecureClassLoader.java:
124)
        at java.net.URLClassLoader.defineClass(URLClassLoader.java:
260)
        at java.net.URLClassLoader.access$000(URLClassLoader.java:56)
        at java.net.URLClassLoader$1.run(URLClassLoader.java:195)
        at java.security.AccessController.doPrivileged(Native Method)
        at java.net.URLClassLoader.findClass(URLClassLoader.java:188)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
        at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:
276)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:251)
        at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:
319)
Aesotericon@5[HelloWorldSwing]$ /home/Aesotericon/Documents/jdk1.6.0/
bin/java .HelloWorldSwing
Exception in thread "main" java.lang.NoClassDefFoundError: /
HelloWorldSwing

As you all see, I have tried several methods of running the program,
but it will not work. I feel like a simpleton, but does anyone have
any suggestions? It seems that java is having a hard time finding
my .class file. I dunno...

J.P.